Abstract: Various systems and methods for adjusting threshold access frequency based on cache pressure are disclosed. The threshold access frequency is adjusted based on a block of data in a storage volume that has an access frequency matching or exceeding the threshold access frequency. The threshold access frequency is used to determine whether the block of data should be inserted into the cache from the storage volume.

Abstract: A system and method for facilitating the use of use processed data from a storage system to perform one or more tasks are disclosed. For example, the method can include identifying data, stored within a storage system, and needed to perform a task. Such data can be stored in a processed form, as a result of such data having been previously processed by the storage system. A determination is made to determine whether the identified data is stored in a processed form. If so, a subsequent determination is made to determine whether the data in the processed form is usable to perform the task. If the data in the processed form is usable to perform the task, a request is generated to request the data in the processed form. The processed data can then be used to perform the task.

Abstract: A computer-implemented method for caching data on virtualization servers may include: 1) providing a virtualization server that executes at least one virtual machine on the virtualization server, 2) intercepting a data operation that includes both basic data and metadata, the data operation being requested by the virtualization server, 3) caching the basic data from the data operation on a solid state drive cache at the virtualization server, and 4) preventing the solid state drive cache from providing metadata from the data operation to the virtualization server. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: Multiple nodes of a cluster have associated non-shared, local caches, used to cache shared storage content. Each local cache is accessible only to the node with which it is associated, whereas the cluster-level shared storage is accessible by any of the nodes. Attempts to access the shared storage by the nodes of the cluster are monitored. Information is tracked concerning the current statuses of the local caches of the nodes of the cluster. Current tracked local cache status information is maintained, and stored such that it is accessible by the multiple nodes of the cluster. The current tracked local cache status information is used in conjunction with the caching functionality to determine whether specific nodes of the cluster are to access their local caches or the shared storage to obtain data corresponding to specific regions of the shared storage.

Abstract: Incremental checkpoint, for use in data replication, track the changes made to a file system after a point in time at which the incremental checkpoint is created. Data replication techniques using the incremental checkpoints may include taking a regular checkpoint of the file system and creating the first time full copy on remote node using the regular checkpoint. Changes made to the file system are then tracked in an incremental checkpoint that are stored on the remote node. The processes of taking the incremental checkpoint and storing the incremental checkpoint are iteratively performed. The first time fully copy and the incremental checkpoints may then be used for data replication, backup, continuous data protection (CDP), or the like.

Abstract: When a loss of connectivity between a first node in a cluster of nodes and a data store is detected, an input/output (I/O) request associated with an application that was executing on the first node is shipped to a second node in the cluster that is in communication with the data store. The application can be gracefully shut down on the first node, and the second node can execute the application and satisfy the I/O request.

Abstract: A method for Quality of Service (QoS) for internal input/output (I/O) using an internal flow mechanism in a storage system is provided. The method includes establishing internal I/O flows corresponding to external I/O flows for one or more computing machines or virtual machines implemented with physical computing resources requesting I/Os. The method includes inheriting service-level agreement (SLA) values from the external I/O flows to the internal I/O flows and determining demands for the external I/O flows and the internal I/O flows. The method includes distributing credits to the internal I/O flows and the external I/O flows according to minimum I/O operations per unit time values, based on the service-level agreement values, and distributing remaining credits to the external I/O flows and the internal I/O flows according to priority and demand of each of the external I/O flows and the internal I/O flows.

Abstract: A method for two level quality of service scheduling for latency and queue depth control in a storage system is provided. The method includes determining queue depth as input/output operations per unit time that a storage subsystem can sustain, for each of a plurality of queues corresponding to storage subsystems in the storage system and determining system capacity as total input and output operations per unit time that the storage system can sustain, based on the queue depth of each of the plurality of queues. The method includes determining whether to accept or deny an input/output request for placement onto an input/output stack, based on a comparison of credits of the input/output request to the system capacity as determined on an ongoing basis, and placing the input/output request from the input/output stack onto one of the plurality of queues based on whether doing so maintains the queue depth of the one of the plurality of queues.

Abstract: The disclosed computer-implemented method for improving quality of service within hybrid storage systems may include (1) monitoring a performance measurement of a hybrid storage system that includes first and second types of storage devices that handle I/O throughput in connection with an application, (2) determining, based at least in part on the monitored performance measurement, an approximate amount of the I/O throughput handled by the first type of storage device over a period of time, (3) determining, based at least in part on the approximate amount of I/O throughput, a rate at which the application is allowed to deliver subsequent I/O throughput to the hybrid storage system over a subsequent period of time, and then (4) regulating, based at least in part on the rate, the subsequent I/O throughput in connection with the application over the subsequent period of time. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A computer-implemented method for identifying access rate boundaries of workloads may include (1) tracking the number of times each region of data within a plurality of regions of data is accessed during a period of time, (2) creating an ordered list of each region of data from the plurality of regions of data, (3) calculating one or more drops in access rates between two or more regions of data in the ordered list, (4) determining that a calculated access-rate drop from a first region of data to a second region of data exceeds a predefined threshold, and (5) calculating a boundary access rate for a workload of data. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A computer-implemented method for enabling write-back caching and replication at different abstraction layers may include (1) identifying a cache abstraction layer that implements write-back caching to selectively cache at least one write to a backing store, (2) identifying a replication abstraction layer that replicates the backing store to a secondary storage system by replicating writes committed to the backing store to the secondary storage system, (3) receiving a request to create a point-in-time image of the backing store at the secondary storage system at a point at which the writes committed to the backing store are point-in-time consistent, (4) committing the cached write to the backing store to ensure that the writes committed to the backing store are point-in-time consistent, (5) marking the point at which the writes committed to the backing store are point-in-time consistent. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A region of memory is logically divided into a number of segments, each of which is logically divided into a number of blocks. Blocks are allocated sequentially. A head pointer and a tail pointer demarcate the section of allocated blocks. As allocated blocks are added, the tail pointer is moved so that it remains at the end of the section of allocated blocks. If the tail pointer is within a threshold distance of the head pointer, then the head pointer is moved from its current position to a new position, and the allocated blocks between the current and new positions are freed (deallocated and/or erased). Thus, writes to the memory can be performed sequentially, and blocks can be freed in advance of when they are actually needed.

Abstract: A periodic checkpoint method for a file system replication source. The method comprises generating a first checkpoint at a first time on a file system replication source and identifying a set of data objects from the replication source that have been modified during a time period between the first time and a subsequent second time. A periodic checkpoint is then generated at the second time on the file system replication source by using the set of data objects.

Abstract: A computer-implemented method for identifying access rate boundaries of workloads may include (1) tracking the number of times each region of data within a plurality of regions of data is accessed during a period of time, (2) creating an ordered list of each region of data from the plurality of regions of data, (3) calculating one or more drops in access rates between two or more regions of data in the ordered list, (4) determining that a calculated access-rate drop from a first region of data to a second region of data exceeds a predefined threshold, and (5) calculating a boundary access rate for a workload of data. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: Data loss prevention systems and methods begin protecting data upon the creation of the data. One such method involves detecting a file system operation targeting data on a storage device. The file system operation creates or modifies the data or a set of permissions associated with the data. In response to detecting the file system operation, the method prevents unauthorized access to the data. The method begins preventing unauthorized access after the detection of the file system operation and before any subsequent read access to the data via the file system.

Abstract: Shared storage access management systems and methods are presented. A method can comprise: performing an endpoint I/O source authority tracking process in which permission of an endpoint I/O source to perform an I/O with at least a portion of an endpoint storage target is tracked at least in part based on a corresponding endpoint I/O source ID value, and performing an I/O operation based upon results of the endpoint I/O source authority tracking process. In one embodiment, the endpoint I/O source ID value is associated with an endpoint I/O source that is a virtual machine. The endpoint I/O source ID value can be unique and can be bound to an endpoint I/O source. In one exemplary implementation, the endpoint I/O source ID value does not depend upon intermediate communication channel characteristics between a corresponding endpoint I/O source and endpoint storage target.

Abstract: A computer-implemented method for facilitating access to shared resources within computer clusters may include (1) identifying a computer cluster, (2) identifying at least one node within the computer cluster that has been selected to execute an application, (3) identifying at least one different node within the computer cluster that has not yet been selected to execute the application, (4) importing a read-write configuration of at least one shared resource to the node, (5) importing a read-only configuration of the shared resource to the different node, (6) determining, after importing the read-only configuration of the shared resource to the different node, that the different node has been selected to execute the application, and then (7) converting, in response to this determination, the different node's read-only configuration of the shared resource to the read-write configuration of the shared resource. Various other systems, methods, and computer-readable media are also disclosed.

Abstract: A computer-implemented method for providing caching for applications with solid-state storage devices may include (1) identifying a plurality of solid-state drives that are available for caching input/output operations, (2) detecting at least one distinguishing hardware property of at least one solid-state drive within the plurality of solid-state drives, (3) determining at least one attribute of an application, and (4) selecting the solid-state drive for caching at least one input/output operation of the application based at least in part on the attribute of the application in combination with the distinguishing hardware property of the solid-state drive. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A computer-implemented method for sending information to guest systems within virtual machines may include receiving, from a guest system within a virtual machine hosted on a host system, a request for virtual device information about a virtual device which may inaccurately represent to the guest system a state of a physical storage device connected to the host system, gathering physical device information via the host system about the physical storage device connected to the host system, determining a mapping of the virtual device within the guest system to the physical storage device connected to the host system, correlating the physical device information with the mapping to determine accurate information about the virtual device and sending the accurate information about the virtual device from the host system to the guest system within the virtual machine. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A computer-implemented method for migrating files to tiered storage systems may include 1) identifying at least one file to migrate from a first file system to a second file system, where the second file system may include a plurality of storage tiers, 2) identifying file metadata associated with the file as stored on the first file system, 3) before writing the file to the second storage system, selecting a storage tier from the plurality of storage tiers based at least in part on the file metadata, and 4) writing the file directly to the selected storage tier within the second file system to avoid moving the file to the selected storage tier after writing the file to the second file system. Various other methods, systems, and computer-readable media are also disclosed.